#!/bin/bash

if [ "$(id -u)" -ne 0 ]; then
    echo "This script must be run as root." >&2
    exit 1
fi

# ------ Settings
Qcow2Dir=/localdisk/backup/qcow2
ShrunkDir=/opt/vm_drive/shrunk
TmpDir=/localdisk/tmp

mkdir -p ${ShrunkDir}
mkdir -p ${TmpDir}
# ------ Settings

Qcow2Files=$(find ${Qcow2Dir} -type f -name "*.qcow2" -mtime -1 -print)
echo "Files to compress:"
echo ${Qcow2Files}
exit

for file in ${Qcow2Files}
do 
    echo "Compressing file ${file}..."
    SparseFile="${ShrunkDir}/$(basename ${file}).sparse"
    ShrunkFile="${ShrunkDir}/$(basename ${file}).shrunk"
    if [ -f ${ShrunkFile} ]
    then
	echo Shrunk file ${ShrunkFile} exists. Skipping...
        continue
    fi
    Cmd="/usr/bin/virt-sparsify"
    Cmd="${Cmd} --check-tmpdir=continue"
    Cmd="${Cmd} --tmp=${TmpDir}"
    Cmd="${Cmd} -q"
    Cmd="${Cmd} ${file} ${SparseFile}"
    Cmd="${Cmd} && /usr/bin/qemu-img convert"
    Cmd="${Cmd} -c"
    Cmd="${Cmd} -O qcow2"
    Cmd="${Cmd} ${SparseFile} ${ShrunkFile}"
    echo ${Cmd}
    eval ${Cmd}

    if [ ${?} -ne 0 ]
    then
        echo "Compression failed. Removing ${ShrunkFile}"
        rm ${ShrunkFile}
    else
        filesz=$(stat -c %s ${file})
        cfilesz=$(stat -c %s ${ShrunkFile})

        ratio=$((cfilesz * 100 / filesz))
        echo "Compression is successful. Compression ratio is ${ratio}%"
        rm ${SparseFile}

        ##
        GuestFile="${ShrunkFile#*.}"
        GuestFile="${GuestFile%.shrunk}"
        Cmd="ln -snf ${ShrunkFile} /opt/vm_drive/${GuestFile}"
        echo ${Cmd}
        eval ${Cmd}
        ##
        Cmd="chown oleg:oleg ${ShrunkFile}"
        echo ${Cmd}
        eval ${Cmd}
    fi
done
    
echo "Done $0 $*"